textproduct: Rapid City

KEY MESSAGES

- Light showers (and a few rumbles of thunder) across portions of northwestern SD this afternoon and evening. Some showers may produce gusty winds.

- Low chance (<10%) for showers over northwestern SD on Friday.

- Clearer skies and mild temps return to finish the work week

DISCUSSION

(This Evening Through Thursday) Issued at 1203 PM MDT Thu Apr 30 2026

Visible satellite shows upper level wave moving through eastern ND. Cu has developed across much of the CWA with a few light radar returns indicating some showers have developed over northwestern SD. A glance at webcams shows that while this activity is high based, precip is indeed making it to the sfc. Have painted light PoPs over portions of northwest SD for early this afternoon to account for this. Showers should continue to develop and move southeastward across the eastern reaches of our CWA through early this afternoon with any stronger cells capable of a few rumbles of thunder and gusts of 30-40 mph. Conditions dry out this evening with a chilly, calm, and mostly clear night on tap.

Another weak shortwave slides across the Northern Plains on Friday. CAMs do show some light showers developing towards central SD Friday afternoon, though forecast soundings are pretty dry. So while there could be a few light, high based showers towards central SD on Friday afternoon, it's unlikely anything will make it to the ground. Therefore have left mentions of PoPs out of the forecast for now.

Ridge builds into the region through early this weekend, bringing dry and warm conditions to the CWA for late Friday into Saturday. Saturday will be warm with highs in the 70s across much of the area. Humidities Saturday afternoon will drop to 15% across southwestern SD with winds gusting up to 25 mph. This would put us near or at Red Flag criteria though the recent precip and fuels in green up preclude any critical fire weather concerns.

Ridge breaks down by Sunday, bringing northwest flow back to the region. Upper level wave slides southeastward from Canada and grazes the CWA on Sunday. Some showers/storms may develop across the Black Hills and western SD on Sunday afternoon as this wave moves through, though not expecting anything severe. Deterministic guidance in good consensus of a Rex Block developing over the western US for the beginning of next week. This would keep our neck of the woods under unsettled northwest flow with mild temperatures and periodic chances for some light precip as a result.

AVIATION

(For the 18Z TAFS Through 18Z Friday) Issued At 1108 AM MDT Thu Apr 30 2026

VFR conditions are expected through the forecast period.

UNR WATCHES/WARNINGS/ADVISORIES

SD...None. WY...None.